It is like claiming that compiling Samba to run in $NEW_PLATFORM suddenly strips Samba of the GPLv3.
And then for the legal part, that's why it's called an exception.
And again, where is the interoperability here? Interoperability exception would apply if there was whitebox cryptography, Nintendo logo-style things or anything else where the only method for the work to run would be to violate copyright of _exactly that_. Under no circumstances you can simply copy & distribute the entire work (or derivates) while claiming "interoperability exception!". It makes utterly no sense.
And then for the interoperability, these decompilation projects are primarily made to target other systems, not the original platform. That's the textbook definition of interoperability.
Let's be real, N64 and the PS1/PS2 (where most of these projects are based) are crumbling old platforms at this point and these projects are sometimes the best way to run games when they exist.
The exception for interoperability only applies to _the minimum required_ for interoperability. You can use this to distribute e.g. decryption code even if copyright would not allow you to do it.
You _cannot_ use this as an excuse to pirate the entire program, much less to create your own derivative work and distribute it!
This is just wishful thinking that comes up every so often in these threads. And then, when Nintendo inevitably shuts everything down, they're the bad guys.